Wire drawing

ABSTRACT

Similar dual step capstan units each having a larger and a smaller diameter section, in which the strand in process provides the driving means from capstan to capstan.

United States Patent Bruestle [4 1 June 20, 1972 [s41 WIRE DRAWING 424,839 4/1890 White ..72/289 824 655 6/1966 Horton ...72/289 7 I t C I Bruestle l0 Edis- I 2] :38 088" 7 3,238,758 3/1966 On.. ..'.....72/289 [22] Filed: April 5, 1971 FOREIGN PATENTS OR APPLICATIONS [2i] Appl. No.: 130,949 1,025,865 4/1966 Great Britain ..72/289 Primary Examiner-Charles W. Lanham CL Assistant ExaminerMichael J. Keenan 531 Field of Search ..72/289; 242/78, 80

[56] References Cited ABSTRACT UNITED STATES PATENTS Similar dual step capstan units each having a larger and a smaller diameter section, in whieh the strand in process pro- 1,95 1,722 3/1934 Brever ..72/289 vidcs the driving means from capstan to capstan. 1,103,609 7/1914 Morgan ..72/383 f I l,579,373 4/1926 Lauren ..72/289 16 Claims, 3 Drawinfigures WIRE DRAWING PRIOR ART Present multiple die wire drawing machines utilize power driven drawblocks or capstans to pull or draw a strand that has been threaded through reducing dies. Depending upon degree of diameter reduction imparted and its corresponding die pull, more or less wraps are placed around the capstan surface to provide the required traction as well as to establish a selective snubbing tension prior to leading the strand on to the next die. Another power driven capstan of increased surface speed receives the previously reduced strand and moves at a velocity corresponding with the elongation imparted in the second die. This arrangement is repeated up to the final or finishing capstan, care being taken to provide for protection of the moving strand against tensions in excess of its capacity at the various reduction stages.

Increased surface speed may be provided for by enlarging the capstan diameters as is the case in a cone type machine where several successively larger steps are mounted on a common shaft, or all capstans may remain of the same diameter but are mounted and driven separately at progressively higher speeds to eflect movement of the strand in the direction of its length. In both instances the strand moves through the wire drawing machine in steps of progressively higher speeds by the effort of a series of power driven capstans. Modern high speed multiple die no'nferrous machines (5,000 F.P.M. or more) demand highest quality gearing generated with precision profiles, dynamically balanced rotating members and assured force feed lubrication to all moving parts. The number of drive members incorporated in the design varies with the manufacturers interpretation of the requirements, but has a pronounced effect upon the operating noise level at high speeds. The passing of the strand, when well lubricated, through the reducing dies does not efi'ect this condition. Todays high speed wire mill is a notoriously noisy place where normal voice level conversation is seldom possible, due mainly to gear noise.

FIELD OF INVENTION This invention proposes a gearless wire drawing system accommodating any practical number of dies and operating with almost complete lack of sound at any speed. Another object of this invention is to provide drawing capstans of equal diameter for all stages. The strand is employed to drive and keep in motion special dual step capstans with diameter differentials to agree with a selected reduction at each die. The absence of gearing materially reduces the unit cost of my machine and allows operation at a considerable reduction in present power requirements. Since several loops of wire are exposed to cooling air at each die position it is intended to eliminate present cooling with spray solution now mandatory when drawing nonferrous metals and so render the cold drawing operation not only quiet but much cleaner as well.

SUMMARY According to the present invention, a power driven entering block with integral drive pulley is provided, which receives the stock from an entering die, a freely mounted dual step capstan unit has a smaller section receiving the strand from said entering block, for at least one half turn, a second reducing die receives the strand finally leaving said entry block, the dual step capstan unit having a larger section receiving the strand from the reducing die, and a second freely mounted capstan unit having a smaller section receiving the strand from the larger section of the first capstan unit for at least one halfturn. Preferably a third reducing die receives the strand finally leaving said larger section of the first dual step capstan section, and the third freely mounted capstan unit has a larger section receiving said strand from said third reducing die. Also, preferably a fourth reducing die receives the strand from said larger section of said third capstan unit, and a finishing capstan receives the strand from the fourth reducing die.

IN THE DRAWINGS FIG. 1 is a plan of the wire drawing machine;

FIG. 2 is a front elevation of the machine shown in FIG. 1; and

FIG. 3 is a plan of a modified machine having a succession of the parts shown in FIGS. 1 and 2.

PREFERRED EMBODIMENT As shown in the drawings, the wire drawing machine comprises a main power drive shafi 10, supported in suitable pillow blocks 1 l and 1 1a. At the front projection near support 11 is a grooved capstan or entering block 12. A wide groove 13 and a series of narrow grooves 14 of equal root dimension are machined into the face of the unit. Beads 15 separate wire loops placed in grooves 14 during operation of the machine. Ahead of block 12 and located in correct line up with wide groove 13 is a die holder assembly 16, anchored to the machine frame.

The strand is threaded through this entering die in the usual manner and then wrapped two or more convolutions around capstan groove or drawing face 13. The strand passes on to a multiple groove driven sheave 17, also equipped with a corresponding number of grooves 18, similar in shape and spacing as grooves 14 in entering block 12. Drive sheave 17 is always smaller in diameter than the drawblock from which it receives its motion, its size being calculated to correspond with the reduction per die agreed upon.

Driven sheave 17 is part of a loosely mounted dual step capstan unit 21 with integral drawing section 20. This second capstan 21 is similar to the entering block 12 in both size and configuration. The strand is wrapped a minimum of one half turn around grooves 18 of sheave 17 as well as narrow grooves 14 of entering block 12. Such multiple looping establishes a firm drive connection causing dual step unit 21 to rotate in fixed captivity with entering capstan 12. Upon leaving the outermost groove 14a of capstan 12 of the strand is guided to a second reducing die 25 by way of deflector pulley 24.

After being threaded through die 25, several wraps are now deposited in wide groove 20a from which the strand progresses to a loosely mounted dual step unit 26. Both units 26 and 21 are exact duplicates and conform in every detail of size and contour. The proposed new type wire drawing machine differs only in the number of dual step capstanswith associated die holders to vary its capacity or to change its die accommodations. Each dual step capstan drives another similar unit at predetermined higher speeds without requiring additional machine elements since the strand itself provides the motive power. The number of driving loops necessary at the entering side of a wire drawing machine is variable and depends upon the total number of reducing dies that follow. It is advantageous to gradually reduce the number of loops towards the finishing end of the machine in accordance with reduced loading.

Continuing the path of the strand from wide groove 20a, the strand is led to smaller step of dual step capstan 26 and again looped between grooved large section 20 of member 21 until all grooves are filled with wire loops. Loosely mounted dual capstan 26 is now under driven control of entering block 12 by way of dual step capstan 21. The final groove 21a returns the strand over deflector pulley 30.

' After the strand is threaded through a third die 31, the wide groove 26a receives several wraps to provide the traction required to overcome the friction in reducing die 31. Capstan 26 now becomes the drive member for finishing capstan 32 through a series of wire loops positioned in grooves as previously explained and provided for on both units. The strand finally leaves groove 26c and is deflected over guide pulley 34 from which it is led to the finishing die 35. Large step 32a of finishing capstan 32 receives the strand and by multiple wrapping provides the necessary pull to cause a strand movement through die 35.

The strand is then directed to a spooling mechanism or any other conventional packaging or receiving means. Both finishing block 32 and dual step capstan 21 are rotatably supported on a parallel shaft 40 secured in pillow blocks 41 and 41a. The snubbing tension imposed upon the strand by the spooling device initiate and maintain wire movement once the drive shaft is set in motion.

Multiple die continuous wire drawing machines may accommodate in excess of l2 die positions. The equivalent machine of my design would embody a minimum of ten identical dual step capstan units in addition to the entering and finishing blocks. Bending stresses are imposed upon shafts l0 and 40 by the driving loops necessitating a spacer or trust bar 42.

To minimize starting tension in the initial group of drive loops it is considered to provide an auxiliary booster drive to a selected intermediate dual step capstan or the finishing capstan. This member may then be permanently secured to the shaft 40 and receive proportionate speed movement through chain drive 50.

Another convenient feature of this new design permits leading the strand from any capstan towards the spooler or packaging device. Each capstan provides a different finishing speed. Machines arranged for entering and drawing from hot rolled rod or large wire sizes require capstans of proportionately larger diameters. Towards the finishing end of the machine all drive members or capstans may be reduced in size.

A schematic illustration of a possible combination of different block sizes is illustrated in FIG. 3. From the larger section of large dual step capstan 26 the strand passes to the smaller section of small dual step capstan 44, from the larger section of which the strand passes to the smaller section of dual step capstan 46. The strand leaving dual step capstan 44 passes through die 48 to the larger section of dual step capstan 46.

In similar fashion the strand passes to dual step capstan 54 freely mounted coaxial to dual step capstan 44. From dual step capstan 54 the strand passes to finishing capstan 56 mounted coaxial with dual step capstan 46. Between capstans the strand passes through dies 52 and 58. All capstans, excepting entering capstan 12 are freely rotatable.

Many two step double die heavy duty rod blocks are now in operation. Such units suffer from the short coming of utilizing a small entering block. My invention permits a single power driven entering block with integral drive pulley and associated freely rotating finishing capstan with driven pulley. Both capstans'may now be of equal diameter.

What is claimed is:

I l. in a wire drawing machine of the class described, a power driven entering capstan comprising a drawing face with integral drive sheaves, a finishing capstan comprising a similar drawing face with integral driven sheaves of a smaller dimension, each capstan comprising a set of sheaves of equal diameter, and a set of sheaves of smaller diameter equal to each other, said finishing capstan being mounted to rotate freely to receive positive accellerated motion from the strand by multiple looping between capstans, and a reducing die preceding each capstan.

2. In a wire drawing machine of the class described, a power driven entering capstan comprising a drawing face with integral drive sheaves, a intermediate capstan comprising a drawing face with integral dual step driver and driven sheaves of different diameters, a finishing capstan comprising a draw- 'ing face with integral driven sheaves of a diameter similar to the small step of the intermediate capstan, each capstan comprising a set of sheaves of equal diameter, and a set of sheaves of smaller diameter equal to each other, said intermediate and finishing capstans being mounted to rotate freely to receive positive accellerated motion from the strand by multiple looping between capstans, and a reducing die preceding each capstan.

3. In a wire drawing machine of the class described, a power driven entering capstan comprising a drawing face with integral drive sheaves, a series of intermediate capstans each comprising a drawing face with integral dual step driver and driven sheaves different diameters, a finishing capstan comprising a drawing face with integral driven sheaves of a diameter similar to the small step of the intermediate capstan, each capstan comprising a set of sheaves of equal diameter, and a set of sheaves of smaller diameter equal to each other, said intermediate and finishing capstans being mounted to rotate freely to receive positive accellerated motion from the strand by multiple looping between capstans, and a reducing die preceding each capstan.

4. Machine as claimed in claim 3 including auxiliary driving means to a selected intermediate capstan.

5. Machine as claimed in claim 3 including auxiliary driving means to the finishing capstan.

6. In a wire drawing machine of the class described a power driven entering capstan comprising a drawing face with integral drive sheaves, a group of intermediate capstans comprising a similar drawing face and dual sheaves sizes, a second group of dual step capstans of reduced diameters, a finishing capstan comprising a drawing face with integral driven sheaves corresponding in size with the second group, each capstan comprising a set of sheaves of equal diameter, and a set of sheaves of smaller diameter equal to each other, all intermediate capstans and the finishing capstan being mounted to rotate freely to receive positive accellerated motion from the strand by multiple looping between capstans, and a reducing die preceding each capstan.

7. Machine as claimed in claim 6 including auxiliary driving means to a selected intermediate capstan.

8. Machine as claimed in claim 6 including auxiliary driving means to the finishing capstan.

9. Wire drawing machine comprising a power driven entering block receiving the strand from a first reducing die;

a freely mounted dual step capstan unit having a smaller section receiving the strand from said entering block for at least one half turn;

a second reducing die receiving the strand finally leaving said entry block;

said dual step capstan unit having a larger section receiving said strand from said second reducing die; and

a second freely mounted capstan unit having a smaller section receiving said strand from said larger section of the first dual step capstan unit for at least one half turn.

10. Wire drawing machine as claimed in claim 9, in which said at least one half turn in each instance comprises a series of loops passing around each in succession for several turns.

11. Wire drawing machine as claimed in claim 9, in combination with a third reducing die receiving the strand finally leaving said larger section of the first dual step capstan section; and

said second freely mounted capstan unit having a larger section receiving said strand from said third reducing die.

12. Wire drawing machine as claimed in claim 11, in combination with a fourth reducing die receiving the strand from said larger section of said second freely mounted dual step capstan unit; and

a finishing capstan receiving said strand from said fourth reducing die.

13. Method of drawing wire, which comprises passing a strand through a first reducing die on through an entering block to a smaller section of a freelymounted dual capstan unit for at least one half turn;

passing the strand finally leaving said entry block to a second reducing die;

passing the strand from said second reducing die to the larger section of said dual step capstan unit; and

passing the strand from said larger section of said first dual capstan unit to the smaller section of a second freely mounted dual capstan unit for at least one half turn.

14. Method as claimed in claim 13, in which said at least one half turn in each instance comprises a series of loops I passing around each in succession for several turns.

15. Method as claimed in claim 14, in which the strand finally leaving said larger section of the first dual step capstan section passes through a third reducing die; and

the strand leaving said third reducing die passes to the larger section of said second freely mounted capstan unit.

16. Method as claimed in claim 15, in which the strand from said larger section of said second freely mounted capstan unit passes to a fourth reducing die; and 5 said strand from said fourth reducing die passes to a finishing capstan.

II I l i l 

1. In a wire drawing machine of the class described, a power driven entering capstan comprising a drawing face with integral drive sheaves, a finishing capstan comprising a similar drawing face with integral driven sheaves of a smaller dimension, each capstan comprising a set of sheaves of equal diameter, and a set of sheaves of smaller diameter equal to each other, said finishing capstan being mounted to rotate freely to receive positive accellerated motion from the strand by multiple looping between capstans, and a reducing die preceding each capstan.
 2. In a wire drawing machine of the class described, a power driven entering capstan comprising a drawing face with integral drive sheaves, a Intermediate capstan comprising a drawing face with integral dual step driver and driven sheaves of different diameters, a finishing capstan comprising a drawing face with integral driven sheaves of a diameter similar to the small step of the intermediate capstan, each capstan comprising a set of sheaves of equal diameter, and a set of sheaves of smaller diameter equal to each other, said intermediate and finishing capstans being mounted to rotate freely to receive positive accellerated motion from the strand by multiple looping between capstans, and a reducing die preceding each capstan.
 3. In a wire drawing machine of the class described, a power driven entering capstan comprising a drawing face with integral drive sheaves, a series of intermediate capstans each comprising a drawing face with integral dual step driver and driven sheaves different diameters, a finishing capstan comprising a drawing face with integral driven sheaves of a diameter similar to the small step of the intermediate capstan, each capstan comprising a set of sheaves of equal diameter, and a set of sheaves of smaller diameter equal to each other, said intermediate and finishing capstans being mounted to rotate freely to receive positive accellerated motion from the strand by multiple looping between capstans, and a reducing die preceding each capstan.
 4. Machine as claimed in claim 3 including auxiliary driving means to a selected intermediate capstan.
 5. Machine as claimed in claim 3 including auxiliary driving means to the finishing capstan.
 6. In a wire drawing machine of the class described a power driven entering capstan comprising a drawing face with integral drive sheaves, a group of intermediate capstans comprising similar drawing face and dual sheaves sizes, a second group of dual step capstans of reduced diameters, a finishing capstan comprising a drawing face with integral driven sheaves corresponding in size with the second group, each capstan comprising a set of sheaves of equal diameter, and a set of sheaves of smaller diameter equal to each other, all intermediate capstans and the finishing capstan being mounted to rotate freely to receive positive accellerated motion from the strand by multiple looping between capstans, and a reducing die preceding each capstan.
 7. Machine as claimed in claim 6 including auxiliary driving means to a selected intermediate capstan.
 8. Machine as claimed in claim 6 including auxiliary driving means to the finishing capstan.
 9. Wire drawing machine comprising a power driven entering block receiving the strand from a first reducing die; a freely mounted dual step capstan unit having a smaller section receiving the strand from said entering block for at least one half turn; a second reducing die receiving the strand finally leaving said entry block; said dual step capstan unit having a larger section receiving said strand from said second reducing die; and a second freely mounted capstan unit having a smaller section receiving said strand from said larger section of the first dual step capstan unit for at least one half turn.
 10. Wire drawing machine as claimed in claim 9, in which said at least one half turn in each instance comprises a series of loops passing around each in succession for several turns.
 11. Wire drawing machine as claimed in claim 9, in combination with a third reducing die receiving the strand finally leaving said larger section of the first dual step capstan section; and said second freely mounted capstan unit having a larger section receiving said strand from said third reducing die.
 12. Wire drawing machine as claimed in claim 11, in combination with a fourth reducing die receiving the strand from said larger section of said second freely mounted dual step capstan unit; and a finishing capstan receiving said strand from said fourth reducing die.
 13. Method of drawing wire, which comprises passing a strand through a first reducing die on through an entering block to a smaller sectioN of a freely mounted dual capstan unit for at least one half turn; passing the strand finally leaving said entry block to a second reducing die; passing the strand from said second reducing die to the larger section of said dual step capstan unit; and passing the strand from said larger section of said first dual capstan unit to the smaller section of a second freely mounted dual capstan unit for at least one half turn.
 14. Method as claimed in claim 13, in which said at least one half turn in each instance comprises a series of loops passing around each in succession for several turns.
 15. Method as claimed in claim 14, in which the strand finally leaving said larger section of the first dual step capstan section passes through a third reducing die; and the strand leaving said third reducing die passes to the larger section of said second freely mounted capstan unit.
 16. Method as claimed in claim 15, in which the strand from said larger section of said second freely mounted capstan unit passes to a fourth reducing die; and said strand from said fourth reducing die passes to a finishing capstan. 